Dinosaur Cove
Encyclopedia
Not to be confused with the children's book series of the same name.

Dinosaur Cove in Victoria, Australia is a fossil bearing site in south-east of the continent where the Otway Ranges meet the sea to the west of Cape Otway, adjacent to Great Otway National Park (map).
The inaccessible ocean-front cliffs include fossil-bearing strata
Stratum
In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...

 that date back to about 106 million years ago (MYA) and has provided discoveries important in research of natural history of dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s in Australia and southern hemisphere as a whole.

Geological time-line

During the Early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 the location was a flood plain within a great rift valley
Rift valley
A rift valley is a linear-shaped lowland between highlands or mountain ranges created by the action of a geologic rift or fault. This action is manifest as crustal extension, a spreading apart of the surface which is subsequently further deepened by the forces of erosion...

 that formed as Australia started to separate northward from Antarctica. Sand, mud and silt deposits covered and sometimes preserved the remains of dead animals and plants. As the rift valley sank, the deposits were overlaid by sediment, which turned to rock under pressure. In the last 30 million years the sediments have been uplifted to form the Otway Ranges and Strzelecki Ranges
Strzelecki Ranges
Strzelecki Ranges, also known as Strzelecki Hills is a low mountain range in the Gippsland region of south-eastern Australia between the Latrobe Valley to the north and Bass Strait to the south...

, bringing them near the surface again.

The richest find of petrified dinosaur bones is confined to narrow thin (up to 0.3 m) layers, most likely ancient stream beds serving as repositories of the bones of smaller animals.

History of discovery

In 1903, geologist William Hamilton Ferguson was mapping the rocky coastal outcrops a few kilometres west of Inverloch
Inverloch, Victoria
Inverloch is a seaside village in Victoria, Australia. It is located on the Bass Highway 143 kilometres southeast of Melbourne, at the mouth of Anderson Inlet, in the Bass Coast Shire and is located close to Australia’s southernmost stand of mangroves...

 and uncovered the first dinosaur fossil ever discovered in Australia.

75 years later, the exploration and excavation of the Dinosaur Cove site was conducted by teams of volunteers overseen by Thomas H. Rich and Patricia Rich. The dinosaur taxa, Leaellynasaura
Leaellynasaura
Leaellynasaura is a genus of small herbivorous ornithischian dinosaur from the Albian stage of the Early Cretaceous, first discovered in Dinosaur Cove, Australia. The type species is Leaellynasaura amicagraphica...

 amicagraphica
and Timimus
Timimus
Timimus is a genus of small coelurosaurian theropod dinosaur, which was originally identified as an ornithomimosaur, from the Early Cretaceous of Australia.-Discovery and species:...

 hermani
, are named for the children of the Riches', Tim and Leaellyn. Heavy mining equipment and dynamite
Dynamite
Dynamite is an explosive material based on nitroglycerin, initially using diatomaceous earth , or another absorbent substance such as powdered shells, clay, sawdust, or wood pulp. Dynamites using organic materials such as sawdust are less stable and such use has been generally discontinued...

 was used to blast away overlying strata to uncover the fossiliferous rock layers in the cliff face.
In the 1980s and 90s Dinosaur Cove yielded hypsilophodont
Hypsilophodont
Hypsilophodonts were small ornithopod dinosaurs, regarded as fast, herbivorous bipeds on the order of 1–2 meters long . They are known from Asia, Australia, Europe, New Zealand, North America, and South America, from rocks of Middle Jurassic to late Cretaceous age...

id-like dinosaurs as Leaellynasaura
Leaellynasaura
Leaellynasaura is a genus of small herbivorous ornithischian dinosaur from the Albian stage of the Early Cretaceous, first discovered in Dinosaur Cove, Australia. The type species is Leaellynasaura amicagraphica...

 amicagraphica
and Atlascopcosaurus
Atlascopcosaurus
Atlascopcosaurus is a genus of herbivorous basal euornithopod dinosaur from the Early Cretaceous of the present Australia....

 loadsi,
and a Coelurosaur, as well as fragments of what may be a caenagnathid (relatives of the Oviraptor
Oviraptor
Oviraptor is a genus of small Mongolian theropod dinosaur, first discovered by the paleontologist Roy Chapman Andrews, and first described by Henry Fairfield Osborn, in 1924...

s). One fossil from this diverse taxa, collectively called the "polar dinosaurs of Australia
Polar dinosaurs in Australia
The South Polar dinosaurs proliferated during the Early Cretaceous while the continent of Australia was still linked to Antarctica to form East Gondwana, a continent that had rifted from Africa and drifted southward. Much of this southern continent lay inside the Antarctic Circle, and the climate...

", has been interpreted as showing possible adaptations to vision in low light conditions and possibly were warm-blooded
Ectotherm
An ectotherm, from the Greek εκτός "outside" and θερμός "hot", refers to organisms that control body temperature through external means. As a result, organisms are dependent on environmental heat sources and have relatively low metabolic rates. For example, many reptiles regulate their body...

; this has been suggested as an explanation for how some of these dinosaurs foraged for food during the polar winter months. It is worth noting that although these dinosaurs lived at polar latitudes, the Cretaceous climate was significantly milder than today, so temperatures within the Antarctic and Arctic Circles were vastly different to the climate at these latitudes today, because the lopsided arrangements of the continents made sea currents and monsoon
Monsoon
Monsoon is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation, but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea...

 winds blow across the polar areas and not round and round them, and so stopped cold pools from developing around the poles.

An astragalus
Talus bone
-External links:* *...

 bone of an ancient relative of Allosaurus
Allosaurus
Allosaurus is a genus of large theropod dinosaur that lived 155 to 150 million years ago during the late Jurassic period . The name Allosaurus means "different lizard". It is derived from the Greek /allos and /sauros...

was discovered at the site, making it the first discovery in the southern hemisphere.
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